Cortisol in the ICU

Keywords

Adrenal hypofunctioncortisolintensive care

Comments

Defining adrenocortical hypofunction in the critically ill remains controversial, and unfortunately this paper is unable to throw much more light on the subject. Many of the patients studied had levels of cortisol that may be considered low (400 nmol/l) for the stressed critically ill patient, and some had corresponding impaired responses to adrenocorticotrophic hormone (ACTH) stimulation. These patients may, therefore, have been experiencing various levels of adrenocortical dysfunction. Whether any of these patients would have benefited from substitution therapy remains unknown, and so a definition for 'adrenal hypofunction in the critically ill' can not be devised until this is answered. This may well be a survival response in the critically ill and substitution therapy may cause harm. A recent prospective study by Annane et al (JAMA 2000, 283:1038-1045 ) showed that elevated basal cortisol levels and a poor response to the ACTH stimulation test, predicted increased mortality in septic shock.

Introduction

The incidence of adrenal hypofunction in the critically ill is unknown as there is conflicting evidence in the literature over expected cortisol measurements in these patients and their response to ACTH. Consequently, it is difficult to decide which patients would benefit from substitution therapy. This study attempts to answer these two questions.